Mainstream Processors from Intel

Intel offers much more processors in the mainstream segment. Besides, they do not stick to only one platform in this price range, but at the same time offer LGA775 and LGA1156 CPUs with principally different microarchitecture.

However, LGA775 platform is already regarded as some kind of vestige of the past, which is kept alive only to get rid of the existing stock. Nevertheless, LGA775 processors sell pretty well for two reasons: first, there are still a lot of systems supporting them; and second, the mainboards for this platform are fairly cheap. There are several modifications of LGA775 processors in the $100-$200 price range, all using the same 45 nm semiconductor die.

Core 2 Duo. These are dual-core processors working at 2.93-3.16 GHz with a shared L2 cache 3 or 6 MB in size. Core 2 Duo use 266 or 333 MHz system bus, so you can use memory working at 1067 or 1333 MHz frequency. Note that the specifications of different Core 2 Duo processor models may differ dramatically. Therefore, the higher-end E8000 series with more advanced features costs considerably more than junior models from the E7000 lineup. However, the difference in performance is indeed noticeable, especially in applications working with large amounts of data.

Core 2 Quad. Quad-core processors in LGA775 form-factor are a combination of two dual-core semiconductor dies sealed inside the same processor packaging. However, Intel adds more differentiation to the family by disabling part of their L2 cache. As a result, there are two processor groups: more affordable ones that fall into the sub-$200 price range and more expensive ones. The part of Core 2 Quad family that we will be discussing today includes processors with 4 or 6 MB L2 cache. So, this cache is physically located on two dies and each half of it is split between the corresponding pair of cores. The clock frequencies of the CPU models that fall into the mainstream price range vary from 2.66 to 2.83 GHz. All Core 2 Quad models support 133 MHz bus.

Frankly speaking, we do not recommend going with the LGA775 platform if you are building a new system. First of all, the platform promotes obviously outdated structure, when the memory controller is inside the chipset rather than the CPU. As a result, there may be additional delays when working with the memory subsystem and in the end it affects the overall system performance quite noticeably. Secondly, LGA775 processors are in most cases slower than LGA1156 CPUs, which are currently very versatile. In fact, the only reason why you may be interested in LGA775 is the availability of very inexpensive Core 2 Quad processors with four computational cores. There are currently no direct competitors for these CPUs among LGA1156 models.

The future of the LGA775 platform doesn’t look too good either. There haven’t been any new processors in this form-factor for quite some time now. Moreover, even the existing models may soon be taken off the price-list and will sink into oblivion. All this means that upgrading a CPU in an LGA775 system may soon become virtually impossible and will result into a complete replacement of the entire platform.

The relatively young LGA1156 platform seems to be much more appealing. Intel currently has several modifications of both: dual- as well as quad-core processors for this platform. All of them are based on Nehalem microarchitecture. Among the major peculiarities of this microarchitecture I would like to point out higher CPU performance, shared L3 cache, integrated memory controller and Hyper-Threading technology support, which presents each physical CPU core to the system as two virtual cores. Moreover, some LGA1156 processors also have an integrated graphics core that can be utilized on Intel H57/H55 based mainboards.

Core i3-500. These are dual-core processors based on a 32 nm semiconductor die that also contain a second additional die – a graphics core. The operating system sees processors like that as quad-core, because they support Hyper-Threading, so that each their core can process two computational threads at the same time. Core i3 processor frequencies fall into the interval from 2.93 to 3.33 GHz. They have a 4 MB L3 cache. The memory controller integrated into the processor supports DDR3 SDRAM with 1067 or 1333 MHz frequency.

Core i5-600. This is another dual-core processor family that has very few differences from the Core i3 the most important one being Turbo Boost technology support. The idea behind this technology implies automatic CPU overclocking (pretty significantly) when only part of the CPU is utilized (in this case one core out of two). Besides, Core i5-600 processors support AES – a set of specific cryptographic instructions, which is disabled in Core i3. The nominal frequencies of the Core i5-600 processor family stretch from 3.2 to 3.6 GHz, however, only models working at up to 3.33 GHz clock speed fall into the mainstream segment we are talking about today. All other specifications of the Core i5-600 processors are exactly the same as those of Core i3-500: Hyper-Threading technology support, 4 MB L3 cache, integrated memory controller supporting DDR3-1067 and DDR3-1333, graphics core integrated into the same CPU packaging.

Core i5-700. This LGA1156 processor family stands a little aside, because these processors use a slightly different 45 nm die with four “real” CPU cores and their price is approaching $200 maximum. According to our criteria, only one CPU from this family could participate in our today’s test session: a less expensive Core i5-750 working at 2.66 GHz frequency. This CPU supports Turbo Boost technology, but Hyper-Threading doesn’t work in it. As a result, the operating system sees it as a quad-core processor, just like it sees Core i5-600. Core i5-700 has an 8 MB L3 cache, and the integrated memory controller is designed to support dual-channel DDR3-1067 and DDR3-1333 SDRAM. I have to say that unlike other Core i5 processor models, the 700 series CPUs do not have an integrated graphics core.

Despite the fact that LGA1156 platform is very mainstream these days, it is not free from several issues. Although Intel offers pretty fast processors for this platform, the multi-GPU configurations built in LGA1156 systems will only work as PCI Express x8 + x8. Therefore, many hardcore gamers are not very excited about this platform. The second drawback of LGA1156 is relatively short anticipated life span of the platform. Although it is less than one year old, in two months Intel is going to introduce LGA1155 platform that should replace LGA1156. It means that we shouldn’t expect any new LGA1156 processors to come out, and the current models will soon be discontinued and vanish from the store shelves.

Let’s sum everything up in the following table listing the detailed specs of all current mainstream Intel processors: